Shipwrecking happens due to the complexity and unpredictability at sea. After a ship sinks in an accident, it is usually unable to refloat or remove the sunken ship immediately as a result of many factors such as technical and weather conditions. Those shipwrecks are usually in or near the navigation routes, resulting in serious navigational dangers for passing ships. Therefore, it is necessary for the competent authorities responsible for navigational beacons and buoys to arrange shipwreck position-indicating buoys immediately after a ship sinks and poses navigational danger to passing ships.
The traditional shipwreck position-indicating buoys are a kind of buoys that have to be arranged by special buoy vessels due to their large volume and large mass, thus the arrangement thereof is difficult. In addition, the traditional shipwreck position-indicating buoys also have the following problems that are difficult to solve:
1. it takes time to complete all processes, from the dispatching of buoy vessels and shipwreck position-indicating buoy vessels by competent authorities to their arrival at the scene of shipwreck, and during this period of time, it is highly possible that secondary accidents take place when passing ships run into the shipwreck if the water depth is not enough at the position of the shipwreck; 2. since shipwrecking usually happens in bad weather conditions, it is difficult to determine the position of the shipwreck at the boundless sea; 3. even if the position of the shipwreck can be determined quickly by competent authorities, the arrangement of buoys may be inevitably influenced by the bad weather conditions; and 4. in case of any shipwreck removal, the position of the shipwreck cannot be indicated accurately by the arranged shipwreck buoy, and consequently, secondary accidents may take place.